Method of multicell battery production using pocketed continuous strip

ABSTRACT

A method of constructing multicell batteries utilizes a continuous web comprising a plurality of structurally connected continuous Zones at least one of which comprises a continuous strip of metal. Deposits of electrodes are placed along the Zones of the continuous web after which the web is cut to structurally disconnect the continuous Zones from each other. Pockets are then indented in a Zone comprising a continuous strip of metal, the indenting being done in a manner which results in the pocketed Zone having the same relative longitudinal length after the indenting as it had before the indenting. Finally, the pocketed Zone is collated into an assembly of battery components which includes at least one other continuous Zone from the web. The indenting may be preceded by the cutting of a slit partially across the Zone to be pocketed, in which case the width of the slits is increased but the center lines of the slits remain in fixed relative longitudinal position by the indenting action. The method is applicable both to webs having metal and plastic laminations and to all metal webs.

United States Patent [191 Oltman et al.

[ Nov. 27, 1973 METHOD OF MULTICELL BATTERY PRODUCTION USING POCKETEDCONTINUOUS STRIP [76] Inventors: John E. Oltman; Kent V. Anderson;

William D. Geverdinck; Max Tronik, all of c/o ESB Incorporated,

P.O. Box 8109, Philadelphia, Pa. 19101 22 Filed: Aug. 27, 1971 [21]Appl. No.: 175,475

[57] ABSTRACT A method of constructing multicell batteries utilizes acontinuous web comprising a plurality of structurally connectedcontinuous Zones at least one of which comprises a continuous strip ofmetal. Deposits of electrodes are placed along the Zones of thecontinuous web after which the web is cut to structurally disconnect thecontinuous Zones from each other. Pockets are then indented in a Zonecomprising a continuous strip of metal, the indenting being done in amanner which results in the pocketed Zone having the same relativelongitudinal length after the indenting as it had before the indenting.Finally, the pocketed Zone is collated into an assembly of batterycomponents which includes at least one other continuous Zone from theweb.

The indenting may be preceded by the cutting of a slit partially acrossthe Zone to be pocketed, in which case the width of the slits isincreased but the center lines of the slits remain in fixed relativelongitudinal position by the indenting action.

The method is applicable both to webs having metal and plasticlaminations and to all metal webs.

8 Claims, 19 Drawing Figures Pmm unum I975 3775.188

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PAIENTEDuuvm ms 3,775,188 SiiEET 6 CF 7 ZoNE*\ zoNE*5 METHOD OFMULTICELL BATTERY PRODUCTION USING POCKETED CONTINUOUS STRIP BACKGROUNDOF THE INVENTION US. Pat. No. 3,708,349 describes a method ofconstructing multicell batteries utilizing a continuous web comprising aplurality of structurally connected continuous Zones No. I, No. 2, andNo. 3. At least one of the Zones of the web comprises a continuous stripof metal. Intermittent deposits of positive electrodes are placed alongone side of each Zone No. I; intermittent deposits of negativeelectrodes are placed along one side of each Zone No. 2; andintermittent deposits of positive and negative electrodes are placedalong each Zone No. 3, each deposit of positive electrode being on theother side of a Zone No. 3 from and substantially opposite a deposit ofnegative electrode. After application of the electrodes the web is cutso that the continuous Zones are structurally disconnected from eachother. The Zones are then collated into an assembly of batterycomponents which includes other continuous Zones from the web. Seals arethen made around the electrodes on the Zones.

In the collation and sealing together of the battery components one ofthe Zones may remain in a plane configuration ln other Zones, however,slight deflections must be made so that satisfactory seals may be madearound the electrodes. This necessary deflection reaches its maximum inat least one of the outermost Zones in the collation.

In order to maintain proper registration among the continuous Zonesduring the collating and sealing steps it is necessary to maintainprecisely the relative longitudinal position of the electrodes alongeach Zone with respect to the electrodes along the other Zone. Errorsalong continuous strips may be cumulative, and the accumulation ofindividually minor longitudinal errors in the collation will, ifrepeated successively, result in such misalignment that continuedcollation and sealing becomes impossible.

With some materials which may be used in batteries, e.g., plastics,fibrous materials, etc., and deflections required in these materials maybe achieved by the forces of the production machinery used in thecollation and sealing, and the related problem of maintaining properregistration of these materials with respect to other battery componentsmay be resolved by the proper control of tension. These solutions toproduction problems become inapplicable, however, with batterycomponents comprising continuous strips of metal foils. With such foilsit may be necessary to produce any required deflections and to take anysteps necessary ,to maintain proper longitudinal registration before themetal is included in the collation.

SUMMARY OF THE INVENTION This invention concerns a method ofconstructing multicell batteries which utilizes a continuous webcomprising a plurality of structurally connected continuous Zones atleast one of which comprises a continuous strip of metal. The continuousweb is cut so that the continuous Zones are continuous strips which arestructurally unconnected from each other. Pockets representing thedeflections required to permit collation and sealing are indented in aZone comprising a continuous strip of metal, the indenting being done ina manner which results in the pocketed Zone having the same relativelongitudinal length after the indenting as it had before the indentingto assure proper longitudinal registration of the pocketed Zone withrespect to other battery components. The pocketed Zone is then collatedinto an assembly of battery components which includes at least one otherZone cut from the web.

Preferably intermittent deposits of electrodes are applied along thecontinuous web before the web is cut to structurally disconnect theZones. The web is defined as comprising at least one Zone No. l, atleast one Zone No. 2, and at least one Zone No. 3 and the electrodes areapplied as follows: intermittent deposits of positive electrodes areplaced along one side of each Zone No. 1; intermittent deposits ofnegative electrodes are placed along one side of each Zone No. 2; andintermittent deposits of positive and negative electrodes are placedalong each Zone No. 3, each deposit of positive electrode being on theother side of a Zone No. 3 and substantially opposite a deposit ofnegative electrode. After the web is cut, pockets are indented aroundthe electrodes in those Zones comprising metal foils which requiredeflections in the collation.

The indenting action may be preceded by the cutting of a slit partiallyacross the Zone to be pocketed, in which case the width of the slits isincreased but the center lines of the slits remain in fixed relativelongitudinal position by the indenting action.-

The method is applicable both to webs having laminates of plastic andmetal and to all metal webs. In webs comprising laminates of plastic andmetal, the electrodes are preferably placed in contact with the plasticrather than the metal. When the electrodes are placed on a metal surfaceof the web, the surfaces of the metal must be selected from metals whichare electrochemically nonreactive with respect to the electrodes andelectrolyte of the battery.

BRIEF DESCRIPTION OF THE DRAWINGS As a prelude to a description of thedrawings it should be remarked that the thicknesses of the members shownin the drawings have been greatly exaggerated for purposes ofillustration. Thicknesses which are typical of those which mightactually be used will be given together with other representativedimensions later in'this account of the invention.

FIG. 1 illustrates a web containing Zones No. I, No. 2 and No. 3 inwhich Zones No. I and No. 2 comprise laminates of electricallyconductive plastic and metal foils. The web, which is symmetrical aboutits center line, contains enough Zones No. 1, No. 2 and No. 3 to permitthe production of two four-cell batteries.

FIG. 2 illustrates the web of FIG. 1 after the deposits of electrodeshave been applied.

FIG. 3 illustrates an end or cross-sectional view of the web shown inFIG. 2.

FIG. 4 shows Zone No. 1 after the web has been cut to structurallydisconnect the Zones from one another, after slits have been cut intothe Zone No. l and before pockets have been indented into Zone No. 1.

FIG. 5 is a plan view of Zone No. I at the stage depicted in FIG. 4.

FIG. 6 shows Zone No. 1 after pockets have been indented into Zone No.l.

FIG. 7 is a plan view of Zone No. l at the stage depicted in FIG. 6.

FIG. 8 illustrates a continuous strip of separator material. Patches ofadhesive are impregnated into the strip, each patch being in the form ofa closed loop. Electrolyte is impregnated into the area of the separatorstrip inside each loop.

FIG. 9 illustrates the pocketed Zone No. 1 being assembled intomulticell batteries.

FIG. 10 illustrates one of the multicell batteries made as shown in FIG.9 after that battery has been cut from the continuous Zones.

FIG. 1 1 illustrates a cross-section of the multicell battery shown inFIG. 10.

FIGS. 12, 13, 14 and 15 illustrate alternatives to the web configurationshown in FIG. 3.

FIG. 16, which represents an alternative to the construction shown inFIG. 11, illustrates a battery in which both outer Zones of the batterycomprise metal foils in which pockets have been indented.-

FIG. 17 shows a web of all metal analagous to the web of metal andplastic laminate shown in FIG. 2.

FIG. 18 illustrates an end or cross-sectional view of the web shown inFIG. 17.

FIG. 19, which is analagous to FIG. 11, illustrates a cross-section ofthe multicell battery made from the web shown in FIG. 17.

DESCRIPTION OF THE PREFERRED EMBODIMENTS It should be remarked that thethicknesses of the members shown in the drawings have been greatlyexaggerated for purposes of illustration. Thicknesses which are typicalof those which might actually be used will be given together with otherrepresentative dimensions later in the description of this invention.

For simplicity the description of the invention will be divided intofour sections. Section 1 will describe the method of making batteriesusing a web comprising composite continuous strips of plastic and metalfoil which is the subject of US. Pat. No. 3,708,349. Section 2 willconcern the relationship of this invention to the process described inSection 1. Section 3 will describe the application of this invention toan all metal web. Section 4 will be directed to the materials which maybe used with the processes described in the other sections.

SECTION 1: WEB COMPRISING LAMINATION OF METAL AND PLASTIC This sectionwill describe how the present invention may be used with the webcomprising a lamination of metal and plastic which is the subject of US.Pat. No. 3,708,349.

FIG. 1 illustrates a web 7 which contains enough Zones No. 1, No. 2 andNo. 3 to permit the production of two four-cell batteries. The webcomprises one continuous strip of electrically conductive plastic 50 andthree other continuous strips of metal foil joined thereto, one of thesethree strips being a metal 60 which is situated in the center of theplastic 50 and the other two strips also being metals 70 which arejoined to the side of the plastic opposite metal 60 and which aresituated near the edges of the plastic. While the edges of the metalfoils 60 and 70 could extend to the edges of their respective Zones, itis preferable to recess them slightly, e.g., 1/ 16 inch from each edgeof the Zone to facilitate cutting or slitting the web apart. While FIG.1 uses dashed and center lines to demarcate the boundaries of Zones No.1, No. 2 and No. 3, it should be understood that those lines are used inthe drawings for purposes of illustration only and no such lines arerequired on an actual web. It will be seen that Zone No. 1 is defined asa composite of a strip of plastic 50 and a metal foil 60, Zone No 2 isdefined as a composite of a strip of plastic 50 and a metal foil 70, andthat Zone No. 3 is defined as a continuous strip of plastic 50. In theweb 7 shown in FIG. 1, the plastic 50 components of Zones No. 1, No. 2and No. 3 are all undivided portions of one wide sheet of plastic.

The construction of multicell batteries begins by placing intermittentdeposits of positive electrodes 20 along the plastic side of Zone No. 1,by placing intermittent deposits of negative electrodes 30 along theplastic side of Zone No. 2, and by placing intermittent deposits ofpositive and negative electrodes 20 and 30 respectively along each ZoneNo. 3 so that each deposit of positive electrode 20 is on the other sideof the Zone No. 3 from and substantially opposite a deposit of negativeelectrode 30. Illustrations of the web 7 after the electrodes have beenso deposited are shown in FIGS. 2 and 3. It will be noted that in allcases the electrodes are narrower than and are centered within the Zonesonto which they were applied, thus leaving perimeters on the Zonesaround the electrodes which will be used in the subsequent sealing step.

After the electrodes have been applied the continuous web 7 is cut sothat the Zones No. 1, No. 2 and No. 3 are continuous strips which arestructurally unconnected from each other. The continuous Zones No. 1,No. 2 and No. 3 are then collated so that at least one Zone No. 3 isbetween a Zone No. 1 and a Zone No. 2, so that the positive electrodesalong Zone No. 1 and the negative electrodes along Zone No. 2 are facingthe inside of the collation, and so that a deposit of positive electrodeon one Zone is opposite a deposit of negative electrode on an adjacentZone. A separator and electrolyte would be placed between each adjacentpair of electrodes in the collation and then the Zones would be sealedtogether around and between the electrode deposits.

An illustration of a separator strip 40 which might be used is shown inFIG. 8. The continuous strip separator material 40 has patches ofelectrically nonconductive adhesive impregnated therein, with each patchbeing in the form of a closed loop inside of which is an area 42 ofseparator material which contains electrolyte. By impregnating theadhesive patches into the separator material first and then adding theelectrolyte to the resultant enclosed areas 42, the electrolyte can beconfined within those areas and prevented from migrating along theseparator strip 40 while at the same time a better, more thoroughadhesive impregnation can be obtained in the separator which results ina superior seal in the assembled battery. Such a concept is furtherdescribed and claimed in US. Pat. No. 3,701,690. As one alternative tothe technique just described, adhesive patches could be impregnated intothe continuous strip of separator material 40 after the electrolyte hasbeen added to the separator. Another step which could be used instead ofbut which is preferably used in conjunction with the adhesiveimpregnations in the separator is to apply patches of adhesive 101around the electrodes on Zones No. 1, No. 2 and No. 3 as shown in FIGS.2, 3 and 5. By themselves these patches l01 would penetrate theseparator strips and produce the desired seals when the collation ofZones and separator strips was pressed together; a sealing technique ofthis latter nature used in the production of single cell batteries isillustrated in US. Pat. No. 3,494,796. It is preferred, however, to usethe patches 101 in combination with the adhesive patches in theseparator strip; it has been found that this combination produces abetter seal than the other alternatives discussed above which utilize aseparator strip.

FIG. 2 also shows a series of dashes 180 being placed across the webbetween the electrodes. Thesedashes, which are purely optional, mayserve as registration devices used in the production machinery. Suchregistration marks should be applied to the web before the web is cut. I

The collation of Zones No. 1, No. 2 and No. 3 and of the preferredseparator strip after the web 7 has been cut to structurally disconnectthe Zones is illustrated in FIG. 9. As shown in FIG. 9, the electrolyteimpregnated areas 42 inside the patches of adhesive 100 in the separatorstrip 40 are positioned so that the impregnated areas are between andoverlay a-positive electrode on one Zone and a negative electrode on anadjacent Zone. The adhesive patches 100 register or mate with thecorresponding adhesive patches 101 on the perimeters of the Zonessurrounding the electrodes. After the desired number of Zones No. 3 andseparator strips 40 have been collated between Zones No. 1 and No. 2 thesealing step is performed. Depending upon the particular sealant 100which is used, the sealing may be achieved by the application of heatand/or pressure, although other satisfactory sealing techniques may alsobe used. The resultant multicell batteries may, if desired, be leftstructurally connected together after the sealing so as to form a chainof multicell batteries which are electrically connected in parallel.Alternatively the collated, sealed continuous strips may be cut so thatthe resultant multicell batteries are structurally and electricallydisconnected from each other; such a discrete battery 5, .illustrated inFIG. 10, may be obtained by cutting along the collated sealed continuousstrips at the dashed, imaginary cut lines shown on the separator strip40 in FIGS. 8 and 9 with an electrically nonconductive cuttinginstrument such as a saphire or ceramic knife, by laser beams or byother suitable techniques. The cutting must be done in a manner so as toavoid producing undesired internal electrical paths within the battery,e.g., so as to prevent the electricity conductive plastic 50 from oneZone from coming into contact with the plastic 50 of another Zone. Aportion of the assembled battery is shown in magnified crosssection inFIG. 11.

If desired the web 7 can be constructed so that the finished, assembledbattery has one of its terminals wrapped around its edge which overlaysthe terminal on the opposite side. For some applications of thebatteries it may be desirable to have both terminals on the same side ofthe battery. Many different modifications can be made in the web toachieve this same net result. One such modification is represented bydashed lines and the designation 70E which appear in FIGS. 1, 2 and 3.This optional extension 70E of the metal foil 70 projects beyond theedge of the plastic component of Zone No. 2, is wrapped around the edgeof the collation and overlays the metal 60 of Zone No. 1. An electricalinsulator must be interposed between the extension 70B and the compositeZone over which it is overlaid; while a nonconductive adhesive 100E ofthe same material as adhesive 100 is shown in the drawings for purposesof illustration, other nonconductive securing materials including avariety of hot melts used in the dry battery industry may be used toalso secure the extension to the underneath Zone, and other nonsecuringnonconductors such as papers, felts, or films may be interposed betweenthe extension and the Zone. The resultant product having the wrappedaround terminal is further described, illustrated, and claimed in US.Pat. No. 3,734,780. The particular construction shown in FIGS. 1, 2 and3 utilizes the relatively good longitudinal conductivity of the metal ascompared with the conductive plastic to minimize the power losses inconducting current around the edge of the battery. A battery with thewrapped around terminal adhered to the negative rather than the positiveend of the battery can be obtained with the web 7 of FIGS. 1 and 2(including metal extensions 70E) by transposing the positive andnegative electrodes and therefore in effect transposing Zones No. 1 andNo. 2 from the positions shown in FIGS. 1 and 2; such transpositionresults in the metallic strip of Zone No. 1 being wider than andextending beyond the edge of the plastic strip of Zone No. 1 and beingadhered to the metal of Zone No. 2. Another modification of the webwhich results in the wrapped around electrode is the extension of theplastic-metal laminates at the edges of the web, rather than theextension of just the metal 70E asshown in FIGS. 1 and 2. Othermodifications of the web which permit the construction of wrapped aroundterminals will be given below in the accounts of alternative webconfigurations or designs. 4

While the web 7 which is used with this invention must have at least oneZone No. l, at least one Zone No. 2, and at least one Zone No. 3,thereare numerous web configurations which meet these requirements andwhich can be used with this invention. FIGS. 12 through 15 illustrate afew of these many different web configurations.

The web 7 shown in FIG. 12 differs from those shown in FIGS. 1, 2 and 3by having five Zones No. 3 on each side of the center line. Each half ofthis web contains enough Zones to permit the construction of a six cellbattery according to the invention.

The web 7 shown in FIG. 13, which is likewise symmetrical about itscenter line, contains enough Zones to permit the construction of fourfour-cell batteries. An optional modification of the web 7, which couldbe made if a "wrapped around terminal of metalconductive plasticcomposite is desired in the finished batteries, is also illustrated. Aspart of this optional medication the plastic 50 and metal could beextended at both edges of the web, as shown by dashed extensions 50E and60E, respectively. An additional aspect of the modification isillustrated near the center of the web by the letter x, which representsthe distance from the edge of the positive electrode 20 to the webcenterline or the edge of Zone No. 1; this distance x could be increasedto include a segment of plastic 50 metal 60 laminate equal in width to50E nand 60E.

FIG. 14 illustrates a web 7 which is symmetrical about its center line.On each side of the center line is one Zone No. 1-, one Zone No. 2, andone Zone No. 3; each half of this web contains enough Zones to permitthe construction of a two cell battery. The web contains six Zones butonly a single strip of electrically conductive plastic 50. As is truewith the web shown in FIG. 1, the web of FIG. 14 has a metal strip 60which is cut down the middle when the web is cut into unconnected Zones.The optional extensions 70E of metal strips 70 are also shown by dashedlines in FIGS. 14.

A very simple configuration of the web 7 having the essentialrequirements is shown in FIG. 15. That web has one Zone No. 1, one ZoneNo. 2 and one Zone No. 3, is symmetrical about its center line, andcontains enough Zones to permit the construction of one twocell battery.The web could, of course, be modified if desired to permit the resultantbattery to have a wrapped around" terminal of either metal ormetalconductive plastic composite.

It was mentioned as a prelude to the description of the drawings thatthe thicknesses of the battery components shown in the drawings havebeen greatly exaggerated for purposes of clear illustration. Thisinvention may be used and is particularly useful in the construction ofvery thin, flat multicell batteries. The dimensions associated with theweb, electrodes and separator illustrated in FIGS. 1 through 3, takenfrom an actual production line design, will serve to illustrate.Referring to FIGS. 1 through 3, the continuous strip of electricallyconductive plastic 50 was a total of 27% inches wide and 2 mils(thousandth of an inch) thick; of this total width, each of the twoZones No. 1 was 2% inches wide, each of the two Zones No. 2 was 2%inches wide, and each of the six Zones No. 3 was 2% inches wide. Themetal strip 60 shown in the center of the web was steel and was 5%inches wide. The metal strips 70 at the two outer edges of the web werealso steel and were each 3% inches wide, of which 2 11/16 inches widthwas joined to the conductive plastic of Zones No. 2 while the remaining1 1/16 inches of metal extended outward as extension 70E to provide fora wrapped around terminal. Each of the metal strips 60 and 70 was 1%mils thick. The electrode deposits 20 and 30, which were centered ineach of the Zones, were approximately 2 l/ 16 inches wide. The electrodedeposits, which might be as much as 20 to 25 mils or more but wouldtypically be l0 mils or less in thickness, were approximately 2 15/ 16inches long (along the length of the Zone) and a space of about itinches clear space was provided between the nearest edges of consecutiveelectrodes. After the electrodes were applied to the web the web was cutby steel slitting wheels to disconnect the Zones from one another. Theseparator strips 40, which were made from nonwoven polyester fabric,were 3 k mils thick and had areas 42 which were centered about andapproximately the same horizontal dimensions as the electrodes.

As is shown in FIG. 11, each plastic, metal and separator member of theassembled battery must be slightly longer and must be deflected slightlymore than the other plastic, metal, and separator members beneath it.This slight increase in length of the separators 40 and the plasticmembers 50 of Zones No. 3 may be achieved by providing enough tension inthose members to stretch them by the required amounts. The deflectionsrequired in these materials to attain the contour shown in FIG. 11 maybe achieved by the forces of the production machinery used in thecollation and sealing. The plastic-metal laminate of Zone No. l, whichmust be increased in length the greatest amount as shown in FIG. 11, maybe indented or pocketed into the desired shape prior to the collatingand sealing steps.

An alternative to the cross-section shown in FIG. 11 appears in FIG. 16.In the alternative illustrated in FIG. 16 the middle Zone of thecollation, a Zone No. 3, is not deflected at all while the remainingZones on each side of the middle Zone are deflected. With thisconstruction there would be a need to pocket both Zone No. 1 and 2before assembling them into the collation, since both of those Zonescontain continuous strips of metal.

The method by which these pockets may be produced, which method is thesubject of this application, will be described in the following section.

SECTION 2: THE POCKETING METHOD In order to maintain proper registrationamong the continuous Zones during the collating and sealing steps it isnecessary to maintain precisely the relative longitudinal position ofthe electrodes along each Zone with respect to the electrodes along eachother Zone. Stated another way, the indenting must be done in a mannerwhich results in the pocketed Zone having the same relative longitudinallength after the indenting as it had before the indenting. Errors alongcontinuous strips may be cumulative, and the accumulation ofindividually minor longitudinal errors in the collation will, ifrepeated successively, result in such misalignment that continuedcollation and sealing becomes impossible.

The problem, therefore, is to provide the necessary deflection in a Zonecomprising a continuous strip of metal while at the same timemaintaining the relative longitudinal length of the Zone containing thecontinuous metal strip.

The problem is solved by this invention in a manner which is bestillustrated in FIGS. 4 through 11. After the electrodes have been placedonto the web and the web has then been cut into structurally unconnectedZones, Zone No. 1 which contains the continuous strip of metal isindented in a manner which maintains the relative longitudinal length ofthat Zone. To accomplish this result it may be desireable to cut a slitpartially across the Zone and between each consecutive pair ofelectrodes along that Zone. Zone No. 1 with such slits therein is shownin FIGS. 4 and 5. As shown in FIG. 5, the slits 165 have a width Zbefore the pockets are indented, with representative dimensions of Zbeing from about 0.060 inches to about 0.062 inches. The slits 165 maybe produced by a composite die which cuts slits by a punch and diearrangement and pockets between the slits in the same stroke with anundersize punch in a die. The longitudinal dimension along Zone No.1between the pair of predetermined positions represented by the centerlines of the slits is designated by y, with a representative magnitudeof y being approximately 3.56 inches (the sum of 2 15/16 and inches, asgiven in the preceding section). It should be pointed out that as usedherein, the word slit has the general meaning given to that term byWebsters dictionary, Le, a long incision or a long, very narrow opening;the term slit is not meant to imply any limitation on the process ormethod of making the long incisions, and different techniques sometimesreferred to in certain industries as slitting, piercing", punching, andothers may all be used to produce the long, very narrow openings.

Referring now to FIGS. 6 and 7, which show Zone No. 1 after the pockets175 have been indented, as well as to FIGS. 9, l0, and l 1, it will beevident that the total length along Zone No. l as measured by followingthe pocketed contour down the middle of that Zone is in excess ofdimension y but that the longitudinal distance along Zone No. l(disregarding the pocketed contour) between the center lines ofconsecutive slits has been maintained at dimension y. This isaccomplished by obtaining the stretching which results from thepocketing in the region of Zone No. 1 between the edge of the electrodeand center line of the slit. As a result of this stretching the width ofthe slits 165 is increased from dimension Z to dimension Z as shown inFIG. 7, with the increase in width typically being from about 0.002inches to about 0.007 inches with pocket depths ranging from about 0.030inches to about 0.045 inches, respectively.

The pocketing can be performed without first slitting Zone No. 1 if theZone can be stretched sufficiently while simultaneously maintaining thedistance y constant. Unfortunately some of the mechanisms used toproduce pocketing do not consistently grip the metal strips in such amanner as to accomplish this result; instead there is a slight slippageof the Zone within the mechanism during the indenting action whichresults in the distance y being reduced rather than being held constant.Where this problem is encountered the slits 165 are useful, for theypermit the slippage of the Zone within the indenting mechanism to beoffset by a stretching or elongation of the Zone outside the indentingaction, with the net result that the desired pocket is achieved whilethe dimension y is held constant.

One other observation should be made to complete the discussion of thepocketing. The indenting mecha nism used to produce the pockets must bestationary with respect to the Zone containing the continuous metalstrip when the pocketing is occurring. One way in which this result canbe obtained is through the use of indenting mechanisms which do nottravel longitudinally in the direction of the Zones travel; in that casea segment of the Zone is brought to a standstill just long enough toundergo pocketing, with take-up loops before and after the pocketingstation letting out and taking up, respectively, the continuous Zone asneeded for the other production steps. An alternative way to achieve thepocketing is with the use of a rotating, endless belt moving at such aspeed that each pocketing mechanism is in a fixed longitudinal positionwith respect to a segment of the Zone while that segment is beingpocketed.

SECTION 3: THE ALL METAL WEB Sections 1 and 2 described how the presentinvention may be used with webs comprising a combination of plastic andmetal. This Section will describe the relevance of the invention to anall metal web. FIGS. 17, 18, and 19 will be referred to in this Section.

FIG. 17 shows an all metal web which is analagous to the one shown inFIG. 2. Its cross-section, shown in FIG. 18, is analagous to thecross-section shown in FIG. 3. A single metal foil is used, andextensions 60E may be provided if the wrapped around terminal is desiredin the finished battery.

The cross-section of the finished battery made from the web illustratedin FIGS. 17 and 18 is shown in FIG. 19. Note that FIG. 19 is analagousto FIG. 11. Note,

however, that in FIG. 19 each of the Zones contains a portion of thecontinuous strips of metal and that only one of these Zones, Zone No. 2,does not require pocketing. Note also that the remaining Zones, ZonesNo. 3 and Zone No. 1, all require pocketing and each by a unique amount.

Starting with the web shown in FIGS. 17 and 18, the Zones could beassembled into a battery having a crosssection analagow to that shown inFIG. I6. In that case one of the Zones No. 3 would require no pocketing,while the remaining Zones Zone No. 1, Zone No. 2 and two Zones No. 3would require pocketing, the amount -of the deflection pocketed intoZone No. 1 being equal to that pocketed into Zone No. 2 and the amountspocketed into the two Zones No. 3 being equal to each other.

The drawings and the accounts given above in Sections 1 and 2 in thisSection thus illustrate the principle that the initial continuous webcomprises a plurality of structurally connected continuous Zones; thatat least one of these Zones comprises a continuous strip of metal; thatthe continuous web is cut so that the continuous Zones are structurallyunconnected from each other; that pockets are indented in at least oneZone comprising a continuous strip of metal, with the indenting beingdone in a manner which results in the pocketed Zone having the samerelative longitudinal length after the indenting as it had before theindenting; and

that the pocketed Zone is collated into an assembly of batterycomponents which assembly includes at least one other Zone cut from theweb.

SECTION-4: THE MATERIALS The process of this invention may utilize awide variety of materials.

The electrically conductive plastic used in the continuous carrier strip50 described in Section 1 may be produced by casting, extrusion,calendaring, or other suitable techniques. The conductive plastics maybe made, for example, from materials such as polymers loaded withelectrically conductive particles and containing various stabilizersand/or plasticizers. The conductive particles may be carbonaceousmaterials such as graphite or acetylene black, or metallic particles mayalso be used. Polymers which by themselves are sufficiently conductivemay also be used. The conductive plastic, whether loaded or unloaded,must be made from a composition which is compatible with othercomponents of the battery. For batteries using LeClanche and moderatelyconcentrated alkaline electrolytes, the conductive plastic may be madefor example, from materials such as polyacrylates, polyvinyl halides,polyvinylidene halides, polyacrylonitriles, copolymers of vinyl chlorideand vinylidene chloride, polychloroprene, and butadiene-styrene orbutadiene-acrylonitrile resins. For batteries using strongly alkalineelectrolytes, polyvinylchloride and polyolefins such as polyethylene andpolyisobutylene may be used in the preparation of the conductiveplastic. For batteries using acid electrolytes such as sulfuric acidpolyvinyl halides, copolymers of vinyl chloride, and vinylidene chloridemay be used.

The metal foils used in the production of Zones No. l and No. 2described in Sections 1 and 2 may be made from such metals as steel,aluminum, lead or zinc. These metals are relatively inexpensive, theyare good electrical conductors, and they can be obtained in foils ofextreme thinness which are substantially free of pinholes. The foils ofthese metals can be purchased in rolls of great length and thus are wellsuited for use in high speed, continuously operating laminatingmachinery. These metals may also be laminated to some conductiveplastics by the application of heat and pressure without requiring anyintermediary adhesives between the layers, or they can be laminatedusing intermediate adhesives. It should be pointed out that while it maybe common in some industries to imply a maximum thickness limitationwhenever the terms foil or metal foil are used, no such limitation isintended as those terms are used herein.

, The positive electrodes 20 may each comprise particles ofelectrochemically positive active material contained in and dispersedthroughout a binder matrix. The positive active material conventionallyis divided ito tiny particles so as to increase the rate at which theelectrochemical reactions can occur by increasing the surface area wherethey occur. The binder increases the electronic conductivity of theelectrode, increases the structural integrity within the positiveelectrode, and adheres the positive electrode to the carrier strip.Since electrolyte must have access to the surface of the active materialparticles, the electrode must be made sufficiently porous so that theelectrolyte may diffuse throughout the electrode rapidly and thoroughly.Preferably the pores in the electrode are produced by the evaporation ofliquid during the construction of the electrode; the evaporating liquidmay be part of a dispersion binder system in which the solid bindercontained in the finally constructed electrode comprises tiny particlesof binder material dispersed throughout and not dissolved in the liquidwhile the electrode is being constructed, or the evaporating liquid maybe part of a solution binder sysem in which the solid binder containedin the finally constructed electrode is dissolved in the liquid which islater evaporated. The porosity of the positive electrodes may beincreased as the discharge rate desired in the battery is increased.Electrodes may also be constructed using various combination of thedispersion and solution systems. Alternatively, the pores might beproduced by the dissolving of a solid which was present duringconstruction of the electrode or by passing gases through or generatinggases within the electrodes at controlled rates during electrodeconstruction. The positive electrodes 20 may, and preferably will, alsocontain amounts of a good electrical conductor such as carbon orgraphite to improve the electrical conductivity between the activematerial particles themselves generally being relatively poor conductorsof electricity. The conductivity of the active material paniclestogether with the conductivity of the binder itself will influence theamounts of conductors added to the electrode. The electrodes 20 may alsocontain if desired small amounts of additional ingredients used for suchpurposes as maintaining uniform dispersion of active materials particlesduring electrode construction, aiding the diffusion of electrolytethrough the pores of the finally constructed electrodes, controllingviscosity during processing, controlling surface tension, controllingpot life, or for other reasons.

The negative electrodes 30 may comprise spray or vapor deposits ofmetals or may comprise tiny particles of metals contained in anddispersed throughout a binder matrix. If the negative electrodes utilizea binder matrix, in general the same considerations regarding thatmatrix apply to the negative electrodes as do for the positiveelectrodes except that no electrical conductor may be needed to achievedesired electrical conductivity between the active material particlessince the negative active materials are generally better conductors thanare the positive materials. When the negative electrodes utilize abinder matrix, the binder system need not be the same as the one used inthe positive electrodes, and even if it is the proportions of binder,active material particles, and other ingredients in the negativeelectrodes may have a different optimum than the proportions ofanalagous ingredients in the positive electrode. When the negativeelectrodes 20 are deposited onto the web in the form of liquiddispersions of active materials and binder, the electrodes should bedried before being further processed. The initial porosity of thenegative electrodes may sometimes be less than that of the positiveelectrodes, since the negative electrode discharge reaction products aresometimes dissolved in the battery electrolyte. The porosity of thenegative electrodes may be increased as the discharge rate desired inthe battery is increased. The negative electrodes 30 may also comprisethin sheets or foils of electrochemically negative material.

If the positive and negative electrodes 20 and 30 respectively have theactive material particles dispersed in a binder matrix as mentionedabove, they may be applied onto the coninuous strips by such techniquesas the rotogravure or reverse roll coating methods used in the printingarts. Such methods are suitable for applying liquids for varyingviscosities onto carriers and may be used with modern, high speed rotaryproduction machinery. Where the electrodes are deposited in the form ofsuch liquids, the electrodes should be dried before being furtherprocessed; the drying can be achieved by passing the web throughappropriate ovens or drying chambers. Other methods of applying thepositive electrodes onto the web includes silk screening, stenciling,and flexographic printing techniques; the particular applicationtechnique selected will depend not only upon the composition of theelectrodes as they are deposited but on such additional factors'as thedesired thickness of the electrodes, the speed at which the continuousZones move with respect to the applicators, and others. It is preferredto use this invention with positive and negative electrode compositionswhich, when placed onto Zones No. 1, No. 2 and No. 3, comprise activematerial particles dispersed in a binder matrix.

It is necessary to place a separator and electrolyte between eachadjacent pair of electrodes in the collation. This requirement may bemet in different ways with different materials. One approach is with theuse of a continuous strip of separator material 40 such as thatillustrated in FIGS. 8 and 9. Such separators may be made from a widevariety of materials including the synthetic fibers, microporous polymersheets, and cellulosic materials which are conventional in batteryconstruction as well as from woven or non-woven fibrous materials suchas polyester, nylon, polyproplene, polyethylene, and glass. Liquidelectrolyte solutions could be impregnated into these separator stripsor patches of viscous, gelled electrolyte could be applied onto one orboth sides of the separator strip. The viscous, gelled electrolytes,which can be made including a wide variety of gelling agents, wouldcontain the needed electrolyte and also adhere or bond to the adjacentelectrodes to produce good conductivity. As another alternative,deposits of viscous, gelled electrolytes could by themselves serve asboth separators and as electrolyte if of proper thickness and/orconsistency, making a distinct separator such as the member 40 shown inH65. 8 and 9 unnecessary. All such alternatives are included within thisinvention as ways of placing a separator and electrolyte between eachadjacent pair of electrodes in the collation.

Several observations should be made in regard to the role of theadhesive patches which provide the seals around the electrodes. Asmentioned earlier, preferably these patches may be impregnated into theseparator strip before the electrolyte is added to that strip. Theadhesive should be applied in liberal quantity so that all of the poresin the separator are completely filled in the area to which the adhesiveis applied and so that there is sufficient excessive adhesive to coatand adhere to the other members being sealed by the patches. Theadhesives should be electrically nonconductive. The adhesives themselvesmay be selected from a wide variety of materials including such adhesivecements as catalyzed uncured epoxy resins, phe nolic resin solutions,ethylene copolymer hot melts, pressure sensitive elastomer mixtures,thermoplastic resin solutions, and natural gums and resins and theirsolutions. Faster and more thorough and complete impregnation of theadhesive into the separator may be achieved with many hot meltcements'by making the impregnations with heat adhesives. The adhesiveswhich may be used may be ones which attain their adhesive quality forthe first time during assembly of the battery as a result of theapplication of pressure, heat, ultrasonics, or other forms of energy.Where gelled electrolytes are used as the only separators betweenadjacent electrodes, sealant deposits 101 of the type shown in FIGS. 2and 3 may be used to achieve the sealing.

While it is preferred to employ the LeClanche electrochemical system(comprising manganese dioxide positive active material, zinc negativeactive material, and an electrolyte comprising ammonium chloride andlorzinc chloride), the multicell battery 5 of this inven tion may employ awide variety of'electrochemical systems including both primary andsecondary systems. Among the positive electrode materials are suchcommonly used inorganic metal oxides as manganese dioxide, lead dioxide,nickel oxyhydroxide, mercuric oxide and silver oxide, inorganic metalhalides such as silver chloride and lead chloride and organic materialscapable of being reduced such as dinitrobenzene and azodicarbonamidecompounds. Among the negative electrode materials are such commonly usedmetals as zinc, aluminum, magnesium, lead, cadmium, and iron. Thisinvention may employ the electrolytes commonly used in the LeClanchesystem (ammonium chloride and/or zinc chloride), various alkalineelectrolytes such as the hydroxides of potassium, sodium and/or lithium,acidic electrolytes such as sulfuric or phosphoric acid, and nonaqueouselectrolytes, the electrolytes of course being chosen to be compatiblewith the positive and negative electrodes.

Among the wide variety of electrochemical systems which may be used inthe multicell battery 5 are those in which the positive electrodescomprise manganese dioxide, the negative electrodes comprise metals suchas zinc, aluminum, or magnesium, and the electrolyte substantiallycomprises an acidic solution of inorganic salts. Another commonly knownsystem useful in the battery 5 is the alkaline manganese system in whichthe positive electrodes comprise manganese dioxide, the negativeelectrodes comprise zinc, and the electrolyte substantially comprises asolution of potassium hydroxide. Other aqueous electrolyte systemsincluding those of nickel-zinc, silver-zinc, mercury-zinc,mercurycadmium, and nickel-cadmium may also be used.

Systems employing organic positive electrodes and acidic electrolytesmay also be used, including rechargeable systems using azodicarbonamidecompound electrodes and LeClanche electrolyte.

With the all metal web described in Section 3, the surfaces of the webmust be selected from metals which are electrochemically nonreactivewith respect to the electrodes and electrolyte of the battery. Asfurther described in U.S. Pat. No. 3,706,616, the metal carrier stripused as the web may comprise: (l) a unimetal which is nonreactive to thepositive and negative electrodes and to the electrolyte within thebattery; (2) a bimetal in which the metal adjacent the positiveelectrode is nonreactive with respect to that electrode and the metaladjacent the negative electrode is nonreactive with respect to thatelectrode; (3) and, a trimetal whose outer two layers are non-reactiveas in (2). The particular metals employed will depend upon theelectrochemical system used in the battery. Metals which are nonreactivein nearly all electrochemical environments in common usage includetitanium, tantalum, and gold; these metals and others which arenonreactive in some but not all electrochemical environments may beused. In general, bimetals have the advantage of permitting a widerselection of materials and of permitting a metals selection based uponthe idea that the metal on one side of the web may be particularlynonreactive with respect to the positive electrodes while the metal onthe other side of the web may be particularly nonreactive with respectto the negative electrodes. Use of trimetals increases the range ofpossibilities by permitting the interior metal to be selected on thebasis of factors such as cost, electrical conductivity, and ease ofpocketing while the two exterior metals may be se lected primarily onthe basis of their electrochemical nonreactivity. Bimetal and trimetalconstructions may be obtained by cladding, plating, flame spraying,vacuum deposition, or by any other suitable means.

We claim:

1. A method of constructing multicell batteries utilizing a continuousweb comprising a plurality of structurally connected continuous Zones,at least one of the Zones comprising a continuous strip of metal, themethod comprising the steps of:

' a. cutting the continuous web so that the continuous Zones arecontinuous strips which are structurally unconnected from each other;

b. indenting pockets in a Zone comprising a continuous strip of metal,each pocket being indented between a pair of predetermined positionsalong the Zone, each pocket being formed while gripping the continuousstrip sufficiently to maintain the distance between the pair ofpredetermined positions constant during the indenting action; and,

c. collating the pocketed Zone into an assembly of battery componentswhich assembly includes at least one other Zone cut from the web.

2. A method of constructing multicell batteries utilizing a continuousweb, the web comprising at least one Zone No. 1, at least one Zone No.2, and at least one Zone No. 3 which are structurally connectedtogether, at least one of theZones comprising a continuous strip ofmetal, the method comprising the steps of:

a. placing intermittent deposits of electrodes along the continuous webby i. placing intermittent deposits of positive electrodes along oneside of each Zone No. 1.

ii. placing intermittent deposits of negative electrodes along one sideof each Zone No. 2, and iii. placing intermittent deposits of positiveand negative electrodes along each Zone No. 3, each deposit of positiveelectrode being on the other side of a Zone No. 3 from and substantiallyopposite a deposit of negative electrode;

b. cutting the continuous web having the electrode deposits thereon sothat the Zones No. 1, No. 2, and No. 3 are continuous strips which arestructurally unconnected from each other;

c. indenting pockets in a Zone comprising a continuous strip of metal,each pocket being indented between a pair of predetermined positionsalong the Zone, each pocket being formed while gripping the continuousstrip sufficiently to maintain the distance between the pair ofpredetermined positions constant during the indenting action:

d. collating the continuous Zones No. 1, No. 2, and No. 3 so that atleast one Zone No. 3 is between a Zone No. 1 and a Zone No. 2, so thatthe positive electrodes along Zone No. l and the negative electrodesalong Zone No. 2 are facing the inside of the collation, and so that adeposit of positive electrode on one Zone is opposite a deposit ofnegative electrode on an adjacent Zone;

e. placing a separator and electrolyte between each adjacent pair ofelectrodes in the collation; and

f. sealing around the electrodes on the Zones.

3. The method of claim 2 in which Zone No. 1 comprises a laminate ofelectrically conductive plastic and metal foil, Zone No. 2 comprises alaminate of electrically conductive plastic and metal foil, and Zone No.3 comprises electrically conductive plastic, the electrodes being placedalong the plastic sides of Zones No. l and No. 2.

4. The method of claim 2 in which each of the Zones No. 1, No. 2, andNo. 3 comprises a metal foil the surfaces of which are electrochemicallynon-reactive with respect to the electrodes and electrolyte of thebattery.

5. A method of constructing multicell batteries utilizing a continuousweb comprising a plurality of structurally connected continuous Zones,at least one of the Zones comprising a continuous strip of metal, themethod comprising the steps of:

a. cutting the continuous web so that the continuous Zones arecontinuous strips which are structurally unconnected from each other;

b. cutting a pair of slits partially across the Zone comprising acontinuous strip of metal;

c. indenting a pocket between the slits in the slitted Zone, theindenting being done in a manner which results in the width of the slitsbeing increased but the center lines of the slits remaining in fixedrelative longitudinal position by the indenting action; and,

d. collating the pocketed Zone into an assembly of battery componentswhich assembly includes at least one other Zone cut from the eb.

6. A method of constructing multicellhtteries utilizing a continuousweb, the web comprising at least one Zone No. l, at least one Zone No.2, and at least one Zone No. 3 which are structurally connectedtogether, at least one of the Zones comprising a continuous strip ofmetal, the method comprising the steps of:

a. placing intermittent deposits of electrodes along the continuous webby i. placing intermittent deposits of positive electrodes along oneside of each Zone No. 1,

ii. placing intermittent deposits of negative electrodes along one sideof each of Zone No. 2, and

iii. placing intermittent deposits of positive and negative electrodesalong each Zone No. 3, each deposit of positive electrode being on theother side of a Zone No. 3 from and substantially opposite a deposit ofnegative electrode;

b. cutting the continuous web having the electrode deposits thereon sothat the Zones No. 1, No. 2, and No. 3 are continuous strips which arestructurally unconnected from each other;

c. cutting a pair of slits partially across the Zone comprising acontinuous strip of metals;

d. indenting a pocket between the slits in the slitted Zone, theindenting being done in a manner which results in the width of the slitsbeing increased but the center lines of the slits remaining in fixedrelative longitudinal position by the indenting action;

e. collating the continuous Zones No. 1, No. 2 and No. 3 so that atleast one Zone No. 3 is between a Zone No. 1 and a Zone No. 2, so thatthe positive electrodes along Zone No. l and the negative electrodesalong Zone No. 2 are facing the inside of the collation, and so that adeposit of positive electrode on one Zone is opposite a deposit ofnegative electrode on an adjacent Zone;

f. placing a separator and electrolyte between each adjacent pair ofelectrodes in the collation; and,

g. sealing around the electrodes on the Zones.

7. The method of claim 6 in which Zone No. 1 comprises a laminate ofelectrically conductive plastic and metal foil, Zone No. 2 comprises alaminate of electrically conductive plastic and metal foil, and Zone No.3 comprises electrically conductive plastic, the electrodes being placedalong the plastic sides of Zones No. l and No. 2. I

8. The method of claim 6 in which each of the Zones No. 1, No. 2, andNo. 3 comprises a metal foil the surfaces of which are electrochemicallynonreactive with respect to the electrodes and electrolyte of thebattery.

2. A method of constructing multicell batteries utilizing a continuousweb, the web comprising at least one Zone No. 1, at least one Zone No.2, and at least one Zone No. 3 which are structurally connectedtogether, at least one of the Zones comprising a continuous strip ofmetal, the method comprising the steps of: a. placing intermittentdeposits of electrodes along the continuous web by i. placingintermittent deposits of positive electrodes along one side of each ZoneNo.
 1. ii. placing intermittent deposits of negative electrodes alongone side of each Zone No. 2, and iii. placing intermittent deposits ofpositive and negative electrodes along each Zone No. 3, each deposit ofpositive electrode being on the other side of a Zone No. 3 from andsubstantially opposite a deposit of negative electrode; b. cutting thecontinuous web having the electrode deposits thereon so that the ZonesNo. 1, No. 2, and No. 3 are continuous strips which are structurallyunconnecteD from each other; c. indenting pockets in a Zone comprising acontinuous strip of metal, each pocket being indented between a pair ofpredetermined positions along the Zone, each pocket being formed whilegripping the continuous strip sufficiently to maintain the distancebetween the pair of predetermined positions constant during theindenting action: d. collating the continuous Zones No. 1, No. 2, andNo. 3 so that at least one Zone No. 3 is between a Zone No. 1 and a ZoneNo. 2, so that the positive electrodes along Zone No. 1 and the negativeelectrodes along Zone No. 2 are facing the inside of the collation, andso that a deposit of positive electrode on one Zone is opposite adeposit of negative electrode on an adjacent Zone; e. placing aseparator and electrolyte between each adjacent pair of electrodes inthe collation; and f. sealing around the electrodes on the Zones.
 3. Themethod of claim 2 in which Zone No. 1 comprises a laminate ofelectrically conductive plastic and metal foil, Zone No. 2 comprises alaminate of electrically conductive plastic and metal foil, and Zone No.3 comprises electrically conductive plastic, the electrodes being placedalong the plastic sides of Zones No. 1 and No.
 2. 4. The method of claim2 in which each of the Zones No. 1, No. 2, and No. 3 comprises a metalfoil the surfaces of which are electrochemically non-reactive withrespect to the electrodes and electrolyte of the battery.
 5. A method ofconstructing multicell batteries utilizing a continuous web comprising aplurality of structurally connected continuous Zones, at least one ofthe Zones comprising a continuous strip of metal, the method comprisingthe steps of: a. cutting the continuous web so that the continuous Zonesare continuous strips which are structurally unconnected from eachother; b. cutting a pair of slits partially across the Zone comprising acontinuous strip of metal; c. indenting a pocket between the slits inthe slitted Zone, the indenting being done in a manner which results inthe width of the slits being increased but the center lines of the slitsremaining in fixed relative longitudinal position by the indentingaction; and, d. collating the pocketed Zone into an assembly of batterycomponents which assembly includes at least one other Zone cut from theweb.
 6. A method of constructing multicell batteries utilizing acontinuous web, the web comprising at least one Zone No. 1, at least oneZone No. 2, and at least one Zone No. 3 which are structurally connectedtogether, at least one of the Zones comprising a continuous strip ofmetal, the method comprising the steps of: a. placing intermittentdeposits of electrodes along the continuous web by i. placingintermittent deposits of positive electrodes along one side of each ZoneNo. 1, ii. placing intermittent deposits of negative electrodes alongone side of each of Zone No. 2, and iii. placing intermittent depositsof positive and negative electrodes along each Zone No. 3, each depositof positive electrode being on the other side of a Zone No. 3 from andsubstantially opposite a deposit of negative electrode; b. cutting thecontinuous web having the electrode deposits thereon so that the ZonesNo. 1, No. 2, and No. 3 are continuous strips which are structurallyunconnected from each other; c. cutting a pair of slits partially acrossthe Zone comprising a continuous strip of metals; d. indenting a pocketbetween the slits in the slitted Zone, the indenting being done in amanner which results in the width of the slits being increased but thecenter lines of the slits remaining in fixed relative longitudinalposition by the indenting action; e. collating the continuous Zones No.1, No. 2 and No. 3 so that at least one Zone No. 3 is between a Zone No.1 and a Zone No. 2, So that the positive electrodes along Zone No. 1 andthe negative electrodes along Zone No. 2 are facing the inside of thecollation, and so that a deposit of positive electrode on one Zone isopposite a deposit of negative electrode on an adjacent Zone; f. placinga separator and electrolyte between each adjacent pair of electrodes inthe collation; and, g. sealing around the electrodes on the Zones. 7.The method of claim 6 in which Zone No. 1 comprises a laminate ofelectrically conductive plastic and metal foil, Zone No. 2 comprises alaminate of electrically conductive plastic and metal foil, and Zone No.3 comprises electrically conductive plastic, the electrodes being placedalong the plastic sides of Zones No. 1 and No.
 2. 8. The method of claim6 in which each of the Zones No. 1, No. 2, and No. 3 comprises a metalfoil the surfaces of which are electrochemically nonreactive withrespect to the electrodes and electrolyte of the battery.